1. Technical Field
The invention generally relates to a microphone array apparatus, and more particularly, to a dereverberation and noise reduction method adapted for a microphone array and an apparatus using the same.
2. Related Art
With the advancement of wireless communication technologies, mobile phones gradually become one of necessary communication tools in people's lives nowadays. However, having a conversation on a mobile phone held in hand while driving easily causes distraction of the driver and may even cause a traffic accident. Therefore, mobile phones with hand free functionality gradually become widely accepted by the drivers.
Although mobile phones with the hand free functionality can decrease conditions where the drivers are distracted when the mobile phones are used inside a vehicle cabin, generally the receiving microphone of the hand free mobile phone is disposed in front of the drivers such as on the driving wheel or around the windscreen. Since the deposition location of the receiving microphones is away from the driver by a certain distance, the receiving microphones normally not only receives audio sounds of the drivers but also other interfering noises such as the noises from the vehicle running engine, the noises from wind shearing through air, the noises of power transmission system and vibration noises between main components and the body of the vehicle, etc. Besides, since the vehicle cabin is a closed space, an echo (or reverberation) is easily generated inside the closed space when the driver is talking. The person at a remote end having a conversation with the driver can simultaneously hear these interfering noises and reverberation, and the overall communication quality is thereby lowered by such a situation. Therefore, how to efficiently receive audio sounds inside the closed space, effectively remove reverberation and decrease noises becomes a major issue.